Two parallel-plate capacitors are identical except that capacitor 1 has vacuum between the plates and capacitor 2 has a dielectric slab of dielectric constant \(\kappa\) filling the space between the plates. The capacitors are connected to identical batteries. Compare the two based on (a) capacitance, \((b)\) charge stored, \((c)\) energy stored, \((d)\) electric field magnitude, and \((e)\) energy density.